Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCHv4 10/11] videobuf2: add begin/end cpu_access callbacks to
 dma-sg
To:     Sergey Senozhatsky <senozhatsky@chromium.org>
Cc:     Hans Verkuil <hans.verkuil@cisco.com>,
        Tomasz Figa <tfiga@chromium.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Kyungmin Park <kyungmin.park@samsung.com>,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Sakari Ailus <sakari.ailus@iki.fi>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Pawel Osciak <posciak@chromium.org>,
        linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20200302041213.27662-1-senozhatsky@chromium.org>
 <20200302041213.27662-11-senozhatsky@chromium.org>
 <f99cd8d2-26a2-acd1-a986-aee66cd2ba12@xs4all.nl>
 <20200307052628.GB176460@google.com>
From:   Hans Verkuil <hverkuil@xs4all.nl>
Message-ID: <8150bc6c-f6a4-fa2c-4e2e-552dcb168df0@xs4all.nl>
Date:   Sat, 7 Mar 2020 10:32:42 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.5.0
MIME-Version: 1.0
In-Reply-To: <20200307052628.GB176460@google.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 07/03/2020 06:26, Sergey Senozhatsky wrote:
> On (20/03/06 15:04), Hans Verkuil wrote:
> [..]
>>> +	/*
>>> +	 * NOTE: dma-sg allocates memory using the page allocator directly, so
>>> +	 * there is no memory consistency guarantee, hence dma-sg ignores DMA
>>> +	 * attributes passed from the upper layer. That means that
>>> +	 * V4L2_FLAG_MEMORY_NON_CONSISTENT has no effect on dma-sg buffers.
>>> +	 */
>>>  	buf->pages = kvmalloc_array(buf->num_pages, sizeof(struct page *),
>>>  				    GFP_KERNEL | __GFP_ZERO);
>>>  	if (!buf->pages)
>>> @@ -470,6 +476,26 @@ static void vb2_dma_sg_dmabuf_ops_release(struct dma_buf *dbuf)
>>>  	vb2_dma_sg_put(dbuf->priv);
>>>  }
>>>  
>>> +static int vb2_dma_sg_dmabuf_ops_begin_cpu_access(struct dma_buf *dbuf,
>>> +					enum dma_data_direction direction)
>>
>> I suggest you use this style to avoid checkpatch warnings:
>>
>> static int
>> vb2_dma_sg_dmabuf_ops_begin_cpu_access(struct dma_buf *dbuf,
>> 				       enum dma_data_direction direction)
> 
> OK, will do.
> 
> Just for information, my checkpatch doesn't warn me:
> 
> $ ./scripts/checkpatch.pl outgoing/0010-videobuf2-add-begin-end-cpu_access-callbacks-to-dma-.patch

We use the --strict option to checkpatch.

Regards,

	Hans

> total: 0 errors, 0 warnings, 46 lines checked
> 
> outgoing/0010-videobuf2-add-begin-end-cpu_access-callbacks-to-dma-.patch has no obvious style problems and is ready for submission.
> 
> 	-ss
>